> ## Documentation Index
> Fetch the complete documentation index at: https://cobo-docs-feature-cobo-cli.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Sign message

> This operation creates a transaction to sign the provided message using cryptographic techniques.

In some scenarios, you want to sign a message for identity authentication or transaction approval. You need to provide details such as the source address, destination address, and the message to be signed. A transaction request for tracking is returned upon successful operation.

You can get the signature result by calling [Get transaction information](https://www.cobo.com/developers/v2/api-references/transactions/get-transaction-information). 

<Note>This operation only applies to transactions from MPC Wallets.</Note>


<RequestExample>
  ```python Python
  import cobo_waas2
  from cobo_waas2.models.create_transfer_transaction201_response import (
      CreateTransferTransaction201Response,
  )
  from cobo_waas2.models.message_sign_params import MessageSignParams
  from cobo_waas2.rest import ApiException
  from pprint import pprint

  # See configuration.py for a list of all supported configurations.
  configuration = cobo_waas2.Configuration(
      # Replace `<YOUR_PRIVATE_KEY>` with your private key
      api_private_key="<YOUR_PRIVATE_KEY>",
      # Select the development environment. To use the production environment, change the URL to https://api.cobo.com/v2.
      host="https://api.dev.cobo.com/v2",
  )
  # Enter a context with an instance of the API client
  with cobo_waas2.ApiClient(configuration) as api_client:
      # Create an instance of the API class
      api_instance = cobo_waas2.TransactionsApi(api_client)
      message_sign_params = cobo_waas2.MessageSignParams()

      try:
          # Sign message
          api_response = api_instance.create_message_sign_transaction(
              message_sign_params=message_sign_params
          )
          print("The response of TransactionsApi->create_message_sign_transaction:\n")
          pprint(api_response)
      except Exception as e:
          print(
              "Exception when calling TransactionsApi->create_message_sign_transaction: %s\n"
              % e
          )

  ```

  ```java Java
  // Import classes:
  import com.cobo.waas2.ApiClient;
  import com.cobo.waas2.ApiException;
  import com.cobo.waas2.Configuration;
  import com.cobo.waas2.Env;
  import com.cobo.waas2.api.TransactionsApi;
  import com.cobo.waas2.model.*;

  public class Example {
    public static void main(String[] args) {
      ApiClient defaultClient = Configuration.getDefaultApiClient();
      // Select the development environment. To use the production environment, replace `Env.DEV` with
      // `Env.PROD
      defaultClient.setEnv(Env.DEV);

      // Replace `<YOUR_PRIVATE_KEY>` with your private key
      defaultClient.setPrivKey("<YOUR_PRIVATE_KEY>");
      TransactionsApi apiInstance = new TransactionsApi();
      MessageSignParams messageSignParams = new MessageSignParams();
      try {
        CreateTransferTransaction201Response result =
            apiInstance.createMessageSignTransaction(messageSignParams);
        System.out.println(result);
      } catch (ApiException e) {
        System.err.println("Exception when calling TransactionsApi#createMessageSignTransaction");
        System.err.println("Status code: " + e.getCode());
        System.err.println("Reason: " + e.getResponseBody());
        System.err.println("Response headers: " + e.getResponseHeaders());
        e.printStackTrace();
      }
    }
  }

  ```

  ```go Go
  package main

  import (
  	"context"
  	"fmt"
  	coboWaas2 "github.com/CoboGlobal/cobo-waas2-go-sdk/cobo_waas2"
  	"github.com/CoboGlobal/cobo-waas2-go-sdk/cobo_waas2/crypto"
  	"os"
  )

  func main() {
  	messageSignParams := *coboWaas2.NewMessageSignParams("f47ac10b-58cc-4372-a567-0e02b2c3d479", "ETH", coboWaas2.MessageSignSource{MpcMessageSignSource: coboWaas2.NewMpcMessageSignSource(coboWaas2.MessageSignSourceType("Org-Controlled"), "f47ac10b-58cc-4372-a567-0e02b2c3d479", "19AR6YWEGbSoY8UT9Ksy9WrmrZPD5sL4Ku")}, coboWaas2.MessageSignDestination{EvmEIP191MessageSignDestination: coboWaas2.NewEvmEIP191MessageSignDestination(coboWaas2.MessageSignDestinationType("EVM_EIP_191_Signature"), "YWFhYQ==")})

  	configuration := coboWaas2.NewConfiguration()
  	// Initialize the API client
  	apiClient := coboWaas2.NewAPIClient(configuration)
  	ctx := context.Background()

  	// Select the development environment. To use the production environment, replace coboWaas2.DevEnv with coboWaas2.ProdEnv
  	ctx = context.WithValue(ctx, coboWaas2.ContextEnv, coboWaas2.DevEnv)
  	// Replace `<YOUR_PRIVATE_KEY>` with your private key
  	ctx = context.WithValue(ctx, coboWaas2.ContextPortalSigner, crypto.Ed25519Signer{
  		Secret: "<YOUR_PRIVATE_KEY>",
  	})
  	resp, r, err := apiClient.TransactionsAPI.CreateMessageSignTransaction(ctx).
  		MessageSignParams(messageSignParams).
  		Execute()
  	if err != nil {
  		fmt.Fprintf(
  			os.Stderr,
  			"Error when calling `TransactionsAPI.CreateMessageSignTransaction``: %v\n",
  			err,
  		)
  		fmt.Fprintf(os.Stderr, "Full HTTP response: %v\n", r)
  	}
  	// response from `CreateMessageSignTransaction`: CreateTransferTransaction201Response
  	fmt.Fprintf(
  		os.Stdout,
  		"Response from `TransactionsAPI.CreateMessageSignTransaction`: %v\n",
  		resp,
  	)
  }

  ```

  ```javascript JavaScript
  const CoboWaas2 = require('@cobo/cobo-waas2');
  // Initialize the API client
  const apiClient = CoboWaas2.ApiClient.instance
  // Select the development environment. To use the production environment, replace `Env.DEV` with `Env.PROD`
  apiClient.setEnv(CoboWaas2.Env.DEV);
  // Replace `<YOUR_PRIVATE_KEY>` with your private key
  apiClient.setPrivateKey("<YOUR_PRIVATE_KEY>");
  // Call the API
  const apiInstance = new CoboWaas2.TransactionsApi();
  const opts = {
    'MessageSignParams': new CoboWaas2.MessageSignParams()
  };
  apiInstance.createMessageSignTransaction(opts).then((data) => {
    console.log('API called successfully. Returned data: ' + data);
  }, (error) => {
    console.error(error);
  });
  ```
</RequestExample>